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POTASSIUM METABISULFITE
ICSC: 1175
Peer-Review Status: 23.10.1995 Validated
Potassium pyrosulfite
Dipotassium disulfite 
CAS #: 16731-55-8 RTECS #: TT4920000
EINECS #: 240-795-3
    Formula: K2S2O5
Molecular mass: 222.3

TYPES OF
HAZARD /
EXPOSURE
ACUTE HAZARDS / SYMPTOMS      PREVENTION      FIRST AID / FIRE FIGHTING
FIRE Combustible under specific conditions. See Notes.  NO open flames.  In case of fire in the surroundings, use appropriate extinguishing media. 
EXPLOSION      
 
EXPOSURE   PREVENT DISPERSION OF DUST! STRICT HYGIENE!   
Inhalation Shortness of breath. Wheezing.  Use local exhaust or breathing protection.  Fresh air, rest. Artificial respiration may be needed. 
Skin   Protective gloves. Protective clothing.  Remove contaminated clothes. Rinse skin with plenty of water or shower. 
Eyes   Wear face shield or eye protection in combination with breathing protection.  First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention. 
Ingestion Diarrhoea. Headache. Vomiting. Weakness.  Do not eat, drink, or smoke during work. Wash hands before eating.  Rinse mouth. Give one or two glasses of water to drink. Rest. 

SPILLAGE DISPOSAL
PACKAGING & LABELLING
Sweep spilled substance into covered containers. If appropriate, moisten first to prevent dusting. Wash away remainder with plenty of water. Personal protection: particulate filter respirator adapted to the airborne concentration of the substance.   
EC Classification
 
UN Classification
 
GHS Classification
 

EMERGENCY RESPONSE SAFE STORAGE
  Dry. Well closed. Keep in a well-ventilated room. 

IMPORTANT DATA
Physical State; Appearance
WHITE CRYSTALLINE POWDER WITH PUNGENT ODOUR. 

Physical dangers
 

Chemical dangers
Decomposes on heating and on burning. This produces toxic and irritating fumes including sulfur oxides. Reacts with acids. This produces toxic and irritating sulfur dioxide. 

Occupational exposure limits
TLV (NOT-ESTABLISHED):. 

Routes of exposure
The substance can be absorbed into the body by inhalation and by ingestion. 

Inhalation risk
Evaporation at 20°C is negligible; a harmful concentration of airborne particles can, however, be reached quickly when dispersed. 

Effects of short-term exposure
Inhalation may cause asthma-like reactions. 

Effects of long-term or repeated exposure
Repeated or prolonged contact may cause skin sensitization. Repeated or prolonged inhalation may cause asthma. 


PHYSICAL PROPERTIES ENVIRONMENTAL DATA
Decomposes at 190°C
Relative density (water = 1): 2.34
Solubility in water: good 
 

NOTES
The compound may catch fire if much heat develops in powdering it.
The symptoms of asthma often do not become manifest until a few hours have passed and they are aggravated by physical effort.
Rest and medical observation are therefore essential.
Anyone who has shown symptoms of asthma due to this substance should avoid all further contact with this substance.
Card has been partly updated in April 2005. 

ADDITIONAL INFORMATION
 

IPCS
International
Programme on
Chemical Safety
WHO ILO EC Prepared in the context of cooperation between the International Programme on Chemical Safety and the European Commission
© IPCS 2004-2012
LEGAL NOTICE Neither the EC nor the IPCS nor any person acting on behalf of the EC or the IPCS is responsible for the use which might be made of this information.


    See Also:
       Toxicological Abbreviations
       Potassium metabisulfite (FAO Nutrition Meetings Report Series 40abc)
       POTASSIUM METABISULFITE (JECFA Evaluation)